CVE-2026-87022

Name of the Vulnerable Software and Affected Versions Apache Tomcat versions 11.0.0-M1 through 11.0.25 Apache Tomcat versions 10.1.0-M1 through 10.1.59 Apache Tomcat versions 9.0.0.M1 through 9.0.121 Apache Tomcat versions 8.5.0 through 8.5.100 Apache Tomcat versions 7.0.56 through 7.0.109

Description Improper handling of length parameter inconsistency allows WebSocket message smuggling when the per-message-deflate extension is used. Per-message-deflate is a compression mechanism used to reduce the amount of data transmitted over a WebSocket connection.

Recommendations Upgrade versions 11.0.0-M1 through 11.0.25 to 11.0.26. Upgrade versions 10.1.0-M1 through 10.1.59 to 10.1.60. Upgrade versions 9.0.0.M1 through 9.0.121 to 9.1.22.